THEME THIS ISSUE Tunnel highways

THEME THIS ISSUE

Tunnel highways

New York's great highway builder Robert Moses loved bridges and hated tunnels. To build a tunnel he said in 1938 was just to dig "a hole in the ground" and when finished it was "merely a tiled vehicular bathroom" ("The Power Broker" Robert Caro, Vintage p641). You can see his last point if a tunnel isn't well ventilated and designed. But Moses who had previously worked political wonders in building New York's parks and highways eventually lost power and respect through his fanatical devotion to building bridges and stopping tunnels. The apogee of his amazing career was his proposed Brooklyn-Battery bridge. Moses had sucessfully bulldozed the bridge project through the New York political machine but the losers went stealthily to Washington DC where President F D Roosevelt, who loathed Moses, got his defense secretary to veto the bridge out of sheer personal spite — with the quite bogus argument that if it were bombed the wrecked bridge could block naval operations in New York harbor. However it is apparent from drawings that the Moses Brooklyn-Battery bridge would have been a visual monstrosity requiring a huge sloping approach ramp that would have destroyed the southern tip of Manhattan as an attractive waterfront. The tunnel that got built instead is far preferable. Moses' tunnel-phobia led him to make wildly pessimistic forecasts of traffic and revenues from this and other New York tunnels, destroying his credibility.

A number of underwater tunnels have been built and some under-mountain tunnels but few under-city tunnels. High costs are a problem. For years the US has been handicapped in tunnel building by federal government prejudice against economical jet fan ventilation systems used elsewhere in the world for tunnels. By insisting on more costly transverse plenum ventilation it has forced American tunnels to be much more costly to build and maintain than needed. The Massachusetts Highway Department recently struck a blow for commonsense when it demonstrated the falsity of federal bans on the use of jet fan ventilation. (see p2) Freed of the need to use traditional plenum ventilation underground highways immediately become 15% or so cheaper to build and since they don't have the low ceiling needed for the air plenum, they become much more pleasant to drive in than the low-ceilinged 'bathrooms' of Moses' imagery.

The motor vehicles of the 1990s are an order of magnitude cleaner in their tailpipe emissions than those of the 1960s which were in turn a several-fold improvement on those of Moses' time. They will get cleaner still in the years ahead so the task of ventilating tunnels is steadily diminishing. The Swedes in particular have made major advances in overcoming the claustrophobic aspects of previous tunnel design, in getting right away from the square tiled bathroom effect. (see in TR soon)

The prejudice against taking highways underground (u/g) remains strong however. Government officials often declare "we have run out of space to build roads" as if that is the end of the matter. Well, there's plenty of space to build underground. And in many cases it is the best solution, especially where the scale and noise of an open-air highway won't be acceptable and where the citizenry passionately oppose demolitions and decry the Chinese wall or 'moat' effects of a proposal.

We've previously reported major u/g toll highway projects:

• Melbourne Australia where investors are building two inner city toll tunnels 3.8km and 1.7km long as part of the City Link project (TR#2 Apr 96 p1)

• Paris where the missing link in the A86 outer beltway will consist of one 10.1km cars-only tunnel and another 7.5km all-vehicles tunnel, both being built by the toll company Cofiroute (TR#5 Aug 96 p1)

• Haifa Israel where proposals are being sought for a concession to build under Mount Carmel tunnels of 3.1km and 1.6km length to provide a bypass of the congested old town and improve overall mobility (TR#7 Sept 95 p6)

• Sydney Australia where developers are floating shares to finance a 6-lane 1.5km toll tunnel under a densely developed inner city area as part of a plan to provide expressway standard access from the airport for the Olympic Games in 2000 (TR#9, Nov 96 p7)

• Tokyo where the world's most expensive u/g highway system is now under construction on the Central Circular Expwy —12km underground in a 18km $13b project (TR#11 Jan 97 p11)

We haven't yet reported other major toll u/g highway projects in Stockholm, Marseilles, Oslo, Singapore, Paris, Toulose, and Hong Kong (on which we are gathering material for future issues of TR). This issue we report magnificent u/g-road projects in Lyon France and Boston Mass USA which demonstrate how imaginative highway design and tunnels can enhance both mobility and the environment and also be financed by loans and equity based on motorists willingness to pay tolls for premium highway service (Boston being a partial exception in financing). These roads are quiet and non-intrusive — discreet highways in keeping with the times. Most of them plan to use variable pricing to keep traffic moving, which keys in with more reports on congestion pricing projects in this issue. It is noteworthy that highways are going underground first in places where there is a strong environmental consciousness of a practical kind — Norway, Sweden, Boston etc. These projects are a standing rebuke to the defeatism of many transport planners who say nothing can be done about the disgrace of urban traffic congestion, that communities won't support new highway construction. Well they will, if it is badly enough needed, and if the solution is imaginatively designed and financed.